Microbial Indoor Air Quality in Early Childhood Education Facilities

Abstract

The aim of this study was to determine the indoor concentrations and type of bacteria and fungi in child care centers and early elementary schools. The samples were collected from indoor air of ten early childhood education facilities in Chonburi. Both concentrations were collected by Microbio sampler. Bacteria and fungi were identified using Gram strain and slide culture, respectively. The microbial concentrations of child care center and early elementary school were analyzed using geometric mean and compared by Mann-Whitney U test. It was found that the average indoor air concentration in total of bacteria and fungi (GM±GSD) were 574±1.8 CFU/m3and 49.0±1.8 CFU/m3, respectively. The average concentrations of bacteria and fungi in child care center were significantly higher than those in early elementary school (p<0.05). When compared with the WHO guideline, the bacterial concentration in both child care centers and early elementary schools (853±1.9 CFU/m3and 421±2.1 CFU/m3, respectively) exceed WHO (<100 CFU/m3) and the fungal concentration in only child care centers (77.0±2.1 CFU/m3) exceed WHO (< 50 CFU/m3). In addition, it was found that the most bacteria and fungi are Gram-positive bacteria and Aspergillus spp., which have concentrations of approximately 80% and 50%, respectively.